SNOSBT0L February   2000  – September 2016 LM340

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
    1.     Available Packages
  3. 3 Description
    1.     Fixed Output Voltage Regulator
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 LM340A Electrical Characteristics, VO = 5 V, VI = 10 V
    6. 6.6 LM340 / LM7805 Electrical Characteristics, VO = 5 V, VI = 10 V
    7. 6.7 LM340 / LM7812 Electrical Characteristics, VO = 12 V, VI = 19 V
    8. 6.8 LM340 / LM7815 Electrical Characteristics, VO = 15 V, VI = 23 V
    9. 6.9 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Output Current
      2. 7.3.2 Current Limiting Feature
      3. 7.3.3 Thermal Shutdown
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Shorting the Regulator Input
      2. 8.1.2 Raising the Output Voltage Above the Input Voltage
      3. 8.1.3 Regulator Floating Ground
      4. 8.1.4 Transient Voltages
    2. 8.2 Typical Applications
      1. 8.2.1 Fixed Output Voltage Regulator
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
    3. 8.3 System Examples
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Heat Sinking DDPAK/TO-263 and SOT-223 Package Parts
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Related Links
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.1.1 Shorting the Regulator Input

When using large capacitors at the output of these regulators, a protection diode connected input to output (Figure 15) may be required if the input is shorted to ground. Without the protection diode, an input short causes the input to rapidly approach ground potential, while the output remains near the initial VOUT because of the stored charge in the large output capacitor. The capacitor will then discharge through a large internal input to output diode and parasitic transistors. If the energy released by the capacitor is large enough, this diode, low current metal, and the regulator are destroyed. The fast diode in Figure 15 shunts most of the capacitors discharge current around the regulator. Generally no protection diode is required for values of output capacitance ≤ 10 μF.